When used correctly, air and HVAC filters can help reduce airborne contaminants, including viruses, in a small building or space. Cleaning or filtering the air alone is not enough to protect people from COVID-19.
Air filtersthat remove small particles, such as high-efficiency particulate air (HEPA) filters, are effective in removing contaminants from the air. The most common appliances that use HEPA filters are portable air purifiers, vacuum cleaners, and heating, ventilation, and air conditioning systems, such as your oven. HEPA stands for “high-efficiency particulate air”.
A HEPA filter can trap and remove microscopic particles, such as COVID-19 viruses, from the air. In that sense, a HEPA air filter can protect against COVID-19 from spreading to someone from an infected person. However, as noted by the EPA, it takes a multi-pronged approach to combating COVID and other viruses. HEPA air filters can effectively remove almost all particles as small as 0.1 micron from the air by capturing 99.7% of 0.3 micron particles and an even greater percentage of larger particles. As the name suggests, these filters are very good for taking things out of the air and holding them so they can't circulate again.
If health problems are the main reason you want to get HEPA air filters, then you should buy them from a highly reputable source. Addition of two HEPA air purifiers that met the Environmental Protection Agency (EPA) recommended Clean Air Delivery Rate (CADR) (reduced overall exposure to simulated exhaled aerosol particles by up to 65% without universal masking). When used together, air filters and HEPA masks reduced exposure to respiratory aerosols by up to 90%.The optimal location for HEPA air purifiers will depend on the unique conditions of each room, but they are likely to be most effective when placed as close to the occupants as possible. A HEPA air filter physically traps particles as circulating air passes through a pleated screen of filtration material.
Kenmore is known for their appliances and HVAC systems, so it's no surprise that they are pioneers in HEPA air filters. Here's a look at some of the best HEPA filters and purifiers for viruses and other potentially harmful contaminants. To investigate the effectiveness of portable HEPA air filters and universal masking in reducing exposure to exhaled aerosol particles, the research team used respiratory simulators to imitate a person with COVID-19 and other uninfected people in a conference room. This NASA study on HEPA filtration is quite technical, but the graph on page 7 and the previous paragraph explain well why HEPA filters are actually almost 100% more efficient at 0.01 microns at capturing ultrafine particles below the HEPA test standard of 0.3 microns. Technically, HEPA is an air filter category based on the size of the particulate medium and the percentage of particles that can be removed from the air as it passes through the filter. While the study provides useful information on the dynamics of respiratory aerosol particles and the effects of HEPA air filters and universal masking, many other factors are also important for disease transmission, including the amount of virus in the particles, the length of time the virus survives in the air and vaccination status of the occupants of the room. Wearing masks without air filters reduced receiver aerosol exposure by 72%, and wearing air filters without masks reduced exposure by up to 65%.
The following is a quick guide on how HEPA filters can play a role in preventing infections by helping to keep viruses out of the air...